System and method for inductive power provision over an extended surface

ABSTRACT

A power providing system for transferring power from an inductive power outlet to an inductive power receiver. The power providing system includes a targeting apparatus capable of detecting the location of the inductive power receiver adjacent to said extended surface and driving a primary inductor in the vicinity of the inductive power receiver. Optionally, the inductive power outlet includes a moving primary inductor which may move into alignment with the receiver. Alternatively, the inductive power outlet includes an array of primary inductors and a primary inductor may be selected in the locality of the inductive power receiver.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.12/757,476 filed Apr. 9, 2010, which is a continuation-in-part of PCTapplication Serial No. PCT/IL2008/001347 filed Oct. 12, 2008, whichclaims the benefit of U.S. provisional application Ser. Nos. 60/960,636filed Oct. 9, 2007; 60/001,106 filed Oct. 31, 2007; 60/996,460 filedNov. 19, 2007; 60/996,592 filed Nov. 27, 2007; 60/996,922 filed Dec. 11,2007; 61/006,037 filed Dec. 17, 2007; 61/008,319 filed Dec. 20, 2007;61/006,132 filed Dec. 26, 2007 and 61/006,238 filed Jan. 2, 2008, thedisclosures of which are hereby incorporated by reference in theirentirety.

TECHNICAL FIELD

The present disclosure relates to an inductive power system and methodwith an inductive power receiver positioned somewhere over an extendedsurface.

BACKGROUND

The provision of electric power where and when needed, is an importantconsideration when constructing buildings. The number and location ofpower outlets required for each room is dependent upon how the room willbe used. Often, however, the future function of the room is not knownduring its construction. Consequently, it is often necessary to relocatepower outlets long after a building is completed, which can be costly.

Conventional power outlets are typically situated at strategic pointsaround the walls of rooms. A ring main to which the power sockets areconnected may be provided. Such a ring main is typically embedded in thewall, and electrical boxes in/on the wall are connected therewith. Thelocation of power outlets is thus determined by the locations of thefixed electrical boxes. Once the wall has been finished, the relocationof power outlets is difficult.

To add or relocate power outlets, additional wiring must be provided.The additional wiring may itself be located within or embedded into thewall by chiseling a groove into the surface thereof, running the wiringalong the groove and rendering over the wiring, with plaster, pointingcompound or the like. Additional power outlets are typically either sunkinto depressions cut into the wall surface or alternatively, protrudingelectrical boxes are screwed or bolted there onto. Another method forrelocating power outlets is to attach a power conduit to the outside ofthe wall and to run wiring through the external conduit, with poweroutlets being connected to the external conduit. Such a solution iscommonly used in schools, colleges, laboratories and other institutions,particularly where the walls are constructed from solid stone, concreteor brick. It will be appreciated that this solution is costly, timeconsuming and unsightly.

U.S. Pat. No. 3,585,565 to Price describes an electrical tape and plugconnector designed to facilitate and simplify the installation ofelectrical wiring. Substantially flat or film conductors are sandwichedbetween insulating layers of protective material. The sandwichconstruction includes a ground conductor insulated from the two mainscurrent carrying conductors. One surface or side of the tape or cable iscoated with a pressure-sensitive adhesive. A three-prong connectoradapts the tape or cable to a utility outlet.

Price's solution allows wiring to lie flat against a wall surface whichmakes the wiring less obtrusive and simpler to install. Howeverinstallation of the utility outlets requires the removal of insulationfrom the conducting tape and the connection of a special plug.Furthermore, the utility outlet once connected cannot be removed withoutexposing the conductor.

An alternative system is described in United States Patent ApplicationNo. 2002/0084096 to Chang. Chang describes an electric wire couplingdevice which includes one or more electric wires having one or moreelectric cables engaged and received in an outer rubber covering. One ormore sockets each has a socket housing and two conductor members securedin the socket housing, which are aligned with the orifices of the sockethousing for receiving plugs. The electric wires and/or the sockets eachhas an adhesive material for attaching to the supporting wall withoutfurther fasteners. The socket may include a side opening for coupling tothe other electric wires.

In Chang's system the power strip and outlets are stuck onto a wallsurface and protrude there from. Aside from being unsightly, if theprotruding sockets are knocked they may become detached from the wall.Because the sockets and wires are supported only by the adhesive and notby additional fasteners, if the sockets become detached from the wallthey will only be supported by the wire itself, thereby posing a safetyhazard.

Conventional electrical sockets have holes therein into which the pinsof corresponding plugs are inserted to form a conductive coupling. Forsafety, the power supplying side of the couple is generally the femalepart, and does not have bare conductive elements protruding therefrom.The plug coupled to the device is the corresponding male part, typicallyhaving bare pins. The size of the pins and holes are such that even asmall child cannot insert his or her fingers thereinto. In high qualitysockets, an earth connection is provided, and, only when a plug with alonger earth pin is inserted there into, is it possible to insert a pin(or anything else) into the holes connected to the current carrying liveand neutral wires. Nevertheless, children do occasionally manage toinsert pencils, pins and other objects into socket holes, sometimes withfatal results. Water can also cause shorting and may result inelectrocution.

Since sockets are unsightly, the number of sockets installed on a wallis generally limited. Often, their position is not appropriate tochanging requirements and extension cords are needed.

For these and other reasons, there is a need for alternative powerprovision than occasionally positioned, conventional socket outletsalong a wall and the present disclosure addresses this need.

SUMMARY

It is an aim of the disclosure to provide a solution to a powerproviding system comprising at least one inductive power outletincorporated into an extended surface such as a bounding surface of aworkspace, the inductive power outlet comprising at least one primaryinductor connectable to a power supply via a driver; the driver forproviding an oscillating voltage supply to the primary inductor; theprimary inductor for inductively coupling with a secondary inductorwired to an electric load. According to various embodiments of thedisclosure, the bounding surface is selected from the group comprising:walls, floors, ceilings, sinks, baths, doors and work surfaces.

Typically, the inductive power outlets are incorporated intoprefabricated materials for incorporating into the bounding surfaces.Optionally, the prefabricated materials are selected from the groupcomprising: plasterboard, paper sheets, wallpaper, plasterers tape,doors, window frames, wall-tiles, fitted cabinets, kitchen counters,sinks, baths, sink surrounds, rugs, fitted carpets, parquet, linoleum,floor-tiles, non-slip matting, tiling, stone, artificial stone andpaving.

According to one embodiment of the disclosure a plasterboard panel isprovided for affixing into the bounding surface, the plasterboard panelcomprising a layer of gypsum sandwiched between two paper sheets and atleast one pair of conductors for connecting the primary inductor to thepower supply, the primary inductor being behind at least one of thepaper sheets.

In various embodiments, the plasterboard panel is additionallycharacterized by at least one feature selected from: a ferromagneticcore for improving flux guidance between the primary inductor and thesecondary inductor; at least one primary inductor being printed onto atleast one paper sheet; the panel being water-resistant; the panelcomprising a heating element; the panel comprising a high resistanceprimary inductor; and the primary inductor comprising an alloy havingrelatively high resistance such that oscillating currents therein,produce a heating effect.

According to another embodiment the disclosure provides a paper sheetfor adhering to the bounding surface; the paper sheet comprising the atleast one primary inductor; and at least one pair of conductors forconnecting the primary inductor to the power supply. Optionally, thepaper sheet may be characterized by at least one feature selected from:the paper sheet being a wallpaper; the primary inductor being adheredonto the back of a dielectric layer; the primary inductor comprising aconducting coil printed onto the paper; and the paper sheet comprisingan adhesive layer for self-adhering to the bounding surface.

In another embodiment of the disclosure a tape is provided for affixingonto the bounding surface, the tape comprising: a first layer having anadhesive surface; a second layer comprising: at least one pair ofelectrical conductors electrically isolated from each other; and the atleast one primary inductor being electrically coupled to the pair ofelectrical conductors; and a third layer overlaying the second layersuch that the pair of electrical conductors and the primary inductor aresandwiched between the first layer and the second layer.

Optionally, the power outlet tape is characterized by at least onefeature selected from the group comprising: the second layer comprisinga two dimensional array of primary inductors; a release layer releasablyengaged to the adhesive surface of the first layer; a coating applied tothe outer face of the third layer, the adhesive surface releasablyengaging with the coating when the power outlet tape is rolled uponitself; the tape comprising a scrim layer of interwoven fibers; and thetape comprising a ferromagnetic core for improving flux guidance betweenthe primary inductor and the secondary inductor.

In still another embodiment of the disclosure, a floor surface for theworkspace is provided, the primary inductor being embedded therein andwired to the power supply via wiring under the floor surface.Optionally, the floor surface is selected from the group comprising:rugs, fitted carpets, parquet, linoleum, floor-tiles, non-slip matting,tiling, stone, artificial stone and paving.

According to a further embodiment of the disclosure, an electricalappliance is adapted to draw power inductively from at least oneinductive power outlet, the electrical appliance comprising at least onesecondary inductor. Typically, the electrical appliance furthercomprising a power storage means, for storing electrical energy forpowering the appliance. Optionally, the power storage means is selectedfrom the group comprising capacitors, accumulators, and rechargeableelectrochemical cells.

In various embodiments, the electrical appliance is selected from thegroup comprising: standing lamps, video recorders, DVD players, papershredders, fans, photocopiers, computers, printers, cooking appliances,refrigerators, freezers, washing machines, clothes dryers, heavymachinery, desk lamps, ambient lighting units, fans, wirelesstelephones, speakers, speaker phones, conference call base units,electric pencil sharpeners, electric staplers, display devices,electrical picture frames, VDUs, projectors, televisions, video players,music centers, calculators, scanners, fax machines, hot plates,electrically heated mugs, mobile phones, hairdryers, shavers,delapidators, heaters, wax-melting equipment, hair curlers, beardtrimmers, bathroom-scales, lights and radios, egg beaters, bread-makers,liquidizers, orange juice extractors, vegetable juicers,food-processors, electric knives, toasters, sandwich toasters, wafflemakers, electrical barbecue grills, slow cookers, hot-plates, deep-fatfryers, electrical frying pans, knife sharpeners, domestic sterilizers,kettles, urns, radios, cassette players, CD players and electricalcan-openers, popcorn makers and magnetic stirrers.

According to yet another embodiment of the disclosure, a system isprovided comprising a power platform that comprises at least onedevice-mounted inductive power outlet for inductively providing power toelectrical loads, the system further comprising at least one secondaryinductor for drawing power inductively from at least one inductive poweroutlet with the power platform being incorporated into an item offurniture. Optionally, the item of furniture is selected from the groupcomprising chairs, tables, workbenches, partitioning walls cabinets andcupboards.

In various embodiments of the disclosure, the inductive power outletcomprises a positioning mechanism for moving the primary inductor behindthe bounding surface. In various embodiments, the inductive power outletis further characterized by at least one feature selected from the groupcomprising: the positioning mechanism comprising a carriage; the primaryinductor being mounted upon at least one of the group comprisingroller-balls, wheels, skis and levitating magnets; the primary inductorbeing affixed to at least one guiding cable; the positioning mechanismbeing motorized; the positioning mechanism being remotely controllableby a user; the primary inductor being affixed to a first magneticelement configured to be pulled by a second magnetic element; thepositioning mechanism further comprising a clutch for engaging theprimary coil to the back face of the bounding surface, and thepositioning mechanism further comprising a release mechanism fordisengaging the primary inductor from the back face of the boundingsurface.

Alternatively or additionally, the positioning mechanism comprises atleast one rail upon which the primary inductor is slideably mounted.Typically, the rail is slideably supported by at least one of the groupcomprising tracks and pulleys.

In other embodiments where the primary inductor is concealed behind asubstantially opaque layer; the system further comprising at least oneindicator for indicating the location of the primary inductor.Optionally, the system is further characterized by at least one featureselected from: the indicator being incorporated within the boundingsurface; the indicator comprising a visual display representing a map ofthe surface, the location of the primary inductor being indicated uponthe map; the indicator further comprising a control panel for adjustingthe location of the primary inductor, the location of the primaryinductor being indicated upon the control panel; the indicatorcomprising at least one transmitter configured to transmit a locatorbeam, the locator beam being detectable remotely; the location of theprimary inductor being determinable by external sensors; and thelocation of the primary inductor being determinable by external sensorsselected from the group comprising: proximity sensors, volume sensors,infra-red sensors, ultrasonic sensors, magnetic sensors, Hall probes,inductance sensors and capacitance sensors.

In certain embodiments, the system includes an indicator comprises anemitter of radiation of a type and intensity capable of penetrating thesubstantially opaque layer and for allowing detection thereof from infront of the substantially opaque layer. Optionally, the system isfurther characterized by at least one feature selected from the groupcomprising: the emitter being incorporated within the primary inductorand the radiation being selected such that the substantially opaquesurface translucent to the radiation; the emitter comprising a lightemitting diode; the emitter comprising the primary inductor; theradiation being detectable by a photodiode; the radiation comprising atleast one of the group comprising: electromagnetic radiation, soundwaves and ultrasonic waves; the radiation comprising infra-redradiation; the infra-red radiation being detectable by a digital camera;and the location of the primary inductor being encoded into a locationsignal and the location signal being transmitted by the radiation.

It is a further aim of the disclosure to provide a protection system forpreventing the power providing system from transmitting power in theabsence of the electric load, the system comprising at least onecircuit-breaker for disconnecting the primary coil from the powersupply. In one embodiment, the protection system further comprises: atleast one primary detector for detecting power transmitted by theprimary inductor; at least one secondary detector for detecting thesecondary inductor inductively coupled to the primary inductor; and atleast one controller in communication with both the primary detector andthe secondary detector, for triggering the circuit-breaker. Optionally,the primary detector is selected from the group comprising: magneticsensors, heat sensors, electromagnetic radiation sensors and Hallprobes.

In other embodiments of the disclosure, the primary inductor of theprotection system radiates at a characteristic frequency f and theprimary detector being configured to detect radiation at frequency f.Optionally, the protection system additionally comprises a modulator fortagging the radiation with a secondary tag indicating that the secondaryinductor is inductively coupled to the primary inductor, wherein thesecondary detector comprises a processor for demodulating the radiationand isolating the secondary signal. Certain embodiments additionallycomprise a modulator for tagging the radiation with a primary taguniquely identifying the primary inductor.

It is a further aim of the disclosure to present a method for preventingan inductive power outlet from transmitting power in the absence of anelectric load, the inductive power outlet comprising at least oneprimary inductor wired to a power supply, for inductively coupling witha secondary inductor wired to the electric load, the method comprisingthe steps of: the primary inductor transmitting power; detecting thatthe primary inductor is transmitting power; checking that the primaryinductor is inductively coupled to the secondary inductor; anddisconnecting the primary inductor from the power supply if no secondaryinductor is detected.

Optionally, Step (b) may be selected from at least one of the steps:communicating a signal from the primary inductor to a controller; anddetecting a radiation emanating from the primary inductor.

Optionally, Step (c) may be selected from at least one of the steps:communicating a signal from the secondary inductor to a controller;encoding a secondary signal within radiation emanating from the primaryinductor; and monitoring the temperature in the vicinity of the primaryinductor and checking for a significant rise in the temperature.

Optionally, Step (d) comprises sending at least one control signal to acontroller indicating that the primary inductor is transmitting powerwith no secondary inductor present, and sending a trigger signal to acircuit-breaker connected between the power supply and the primaryinductor.

Still further embodiments disclose a power providing system comprising atargeting apparatus comprising a location monitor configured to indicatethe location of the inductive power receiver. Optionally, the targetingapparatus comprises: a location monitor configured to monitor thelocation of the inductive power receiver; and a driver configured toprovide an oscillating voltage supply to the at least one local primaryinductor in the vicinity of the secondary inductor.

In embodiments wherein the inductive power outlet comprises an array ofprimary inductors distributed behind the extended surface, the drivermay be further configured to select the local primary inductor from thearray the local primary inductor being in the vicinity of the secondaryinductor.

In other embodiments, the inductive power outlet may comprise apositioning mechanism for moving a movable primary inductor behind theextended surface and the driver is further configured to direct themovable primary inductor into the vicinity of the secondary inductor.

Optionally, the location monitor comprises an array of tracking-signaldetectors associated with the inductive power outlet, thetracking-signal detectors configured to detect a signal emitted by atleast one tracking-signal emitter carried by the inductive powerreceiver, and a processor configured to calculate the location of theinductive power receiver using triangulation. Advantageously, thelocation monitor may further comprise a timing-detector configured toreceive a fast-traveling tracking-signal emitted by a secondtracking-signal emitter carried by the inductive power receiver.

It is a further aspect to teach a method for transferring power from aninductive power outlet to an inductive power receiver adjacent to anextended surface, the method comprising the steps: step (I)—providing atleast one primary inductor behind the an extended surface; step(II)—locating the inductive power receiver; and step (IV)—providing anoscillating voltage supply to at least one primary inductor coupled to asecondary inductor integral to the inductive power receiver.

Step (I) of the method may variously comprise: step (I′)—providing anarray of primary inductors distributed behind the extended surface, andthe method may comprise the additional step: step (III)—selecting atleast one local primary inductor from the array, the local primaryinductor being in the vicinity of the secondary inductor.

Alternatively, step (I) of the method may comprise: step (I″)—providingat least one movable primary inductor behind the extended surface, themethod comprising the additional step: step (III′)—directing the movableprimary inductor into the vicinity of the secondary inductor.

Optionally, step (II) of locating the inductive power receiver mayinclude the substeps: step (Ha)—the inductive power receiver emitting atleast one tracking-signal; step (IIb)—detecting the tracking-signal byan array of tracking-signal detectors; and step (IIc)—calculating thelocation of the inductive power receiver using triangulation.

BRIEF DESCRIPTION OF THE DRAWINGS

For a better understanding of the disclosure and to show how it may becarried into effect, reference will now be made, purely by way ofexample, to the accompanying drawings.

With specific reference now to the drawings in detail, it is stressedthat the particulars shown are by way of example and for purposes ofillustrative discussion of the various embodiments of the presentdisclosure only, and are presented in the cause of providing what isbelieved to be a useful and readily understood description of theprinciples and conceptual aspects of the disclosure. In this regard, noattempt is made to show structural details of the disclosure in moredetail than is necessary for a fundamental understanding of thedisclosure; the description taken with the drawings making apparent tothose skilled in the art how the several forms of the disclosure may beembodied in practice. In the accompanying drawings:

FIG. 1 is a schematic diagram of a corner of a room, incorporating apower providing system according to one embodiment of the presentdisclosure;

FIG. 2 is a schematic representation of a plaster board wall panelincluding a plurality of primary inductive coils and connecting wiresfor coupling to a mains power supply;

FIG. 3 is a schematic representation of a wall incorporating theplasterboard wall panel of FIG. 2;

FIG. 4 is a schematic representation of a wallpaper including aplurality of primary inductive coils and connecting wires for couplingto a mains power supply;

FIG. 5 is a schematic representation of a wall coated with the wallpaperof FIG. 4;

FIG. 6 is a schematic representation of a wall incorporating primaryinductive coils connected to a control box;

FIG. 7 shows an exemplary configuration of the electrical componentsembedded in a section of walling according to a further embodiment ofthe disclosure;

FIG. 8 a is a schematic representation of a roll of power outlet tape;

FIG. 8 b is a schematic representation of a second, wider power outlettape having a two dimensional array of primary inductive coilsthereupon;

FIG. 9 a is a schematic representation of the power outlet tape of FIG.8 a being applied to a wall;

FIG. 9 b is a schematic representation of various appliances providedwith dedicated inductive power adaptors, mounted upon the completed wallof FIG. 9 a;

FIG. 9 c is a schematic representation of an inductive power adaptormounted to a wall;

FIG. 10 a shows a first configuration of the electrical components ofthe power outlet tape;

FIG. 10 b shows a second configuration of the electrical components ofthe power outlet tape;

FIG. 11 shows an under-floor power providing system in accordance with afurther embodiment of the present disclosure;

FIG. 12 a-f are schematic representations of various embodiments ofelectrical appliances provided with secondary coils, adapted to receivepower from inductive outlets;

FIG. 13 a-d are schematic representations of further embodiments ofelectrical appliances, adapted to receive power from inductive outlets;

FIG. 14 a is a schematic representation of a surface incorporating amovable power outlet, with a portable computer inductively coupledtherewith according to another embodiment of the current disclosure;

FIG. 14 b is a cross section through a surface layer behind which apower outlet is mounted upon a first embodiment of a positioningmechanism;

FIG. 15 a is a schematic representation of a wall including a linearrail behind the skirting board thereof to which a power outlet isslidably mounted and free to be moved by a second embodiment of apositioning mechanism;

FIG. 15 b is a schematic representation of two power outlets slidablymounted to an extended rail covering a wall;

FIG. 15 c is a schematic representation of a third embodiment of apositioning mechanism wherein a power outlet is mounted upon anadjustable H-frame behind a wall;

FIG. 15 d is a schematic representation of a fourth embodiment of apositioning mechanism wherein a power outlet is movable by four guidingcables behind a surface;

FIGS. 16 a and 16 b show sections through a movable inductive outletincluding a clutch mechanism engaged and disengaged to the surface;

FIG. 17 a is a schematic representation of a concealed power outlet andan indicator incorporated into a surface for indicating the location ofa primary coil concealed behind the surface;

FIG. 17 b is a schematic representation of a computer resting upon thesurface of FIG. 17 a and being powered by the concealed primary coil;

FIG. 17 c is a schematic representation of an alternative power outlet,wherein an adjustable primary coil is concealed behind a wall andcontrollable remotely by a control panel which indicates the location ofthe primary coil;

FIG. 18 a is a schematic representation of a power outlet, wherein alight emitting diode transmits a location beam which is received by acamera of a mobile phone;

FIG. 18 b is a block diagram representing a power outlet according toanother embodiment of the disclosure, wherein a primary coil isconfigured to transmit a locator beam, carrying an encoded signalidentifying the location of the primary coil, to a receiver;

FIG. 18 c is a schematic representation of a location monitor for usewith embodiments of the disclosure;

FIG. 18 d is a schematic representation of an embodiment of the locationmonitor incorporated into an extended power transmission surface havingmultiple inductive outlets;

FIG. 18 e is a schematic representation of another embodiment of thelocation monitor incorporated into an alternative extended powertransmission surface having a movable inductive power outlet;

FIG. 19 is a block diagram of a power-leak prevention system for use ina power providing system according to another embodiment of the presentdisclosure;

FIG. 20 a is a schematic diagram of an inductive power outlet protectedby a local leak prevention system, and a secondary coil, wired to anelectric load, inductively coupled thereto, in accordance with anotherembodiment of the present disclosure;

FIG. 20 b is a schematic diagram of the inductive power outlet of FIG.20 a without a secondary coil inductively coupled thereto;

FIG. 21 is a schematic diagram of a plurality of inductive power outletsprotected by a remote leak prevention system according to a furtherembodiment of the present disclosure;

FIG. 22 is a flow-chart illustrating a method for preventing aninductive power outlet from transmitting power in the absence of anelectric load coupled therewith, according to still another embodimentof the present disclosure; and

FIG. 23 is a flowchart showing the main steps in a method fortransferring power from an inductive power outlet to an inductive powerreceiver placed adjacent to an extended surface.

DETAILED DESCRIPTION

As those of ordinary skill in the art will understand, various featuresof the present disclosure as illustrated and described with reference toany one of the Figures may be combined with features illustrated in oneor more other Figures to produce embodiments of the present disclosurethat are not explicitly illustrated or described. The combinations offeatures illustrated provide representative embodiments for typicalapplications. However, various combinations and modifications of thefeatures consistent with the teachings of the present disclosure may bedesired for particular applications or implementations.

Reference is now made to FIG. 1 showing a schematic diagram of a powerproviding system according to an exemplary embodiment of the presentdisclosure. A workspace 1, such as a corner of a room, bounded by walls2 a, 2 b, a ceiling 2 c and a floor 2 d, contains a variety ofelectrical appliances 4, such as a television set 4 a and a lightfixture 4 b, for example. Such electrical appliances 4 are adapted todraw power from inductive power outlets 6. It is a particular feature ofone aspect of the disclosure that inductive power outlets areincorporated into the bounding surfaces 2 of the room, such as thewalls, ceiling and flooring thereof.

Inductive power coupling allows energy to be transferred from a powersupply to an electric load without a conduction path being providedtherebetween. A power supply is wired to a primary inductor and anoscillating electric potential is applied across the primary inductorwhich induces an oscillating magnetic field. The oscillating magneticfield may induce an oscillating electrical current in a secondaryinductor placed close to the primary inductor. In this way, electricalenergy may be transmitted from the primary inductor to the secondaryinductor by electromagnetic induction without the two inductors beingconductively connected. When electrical energy is transferred from aprimary inductor to a secondary inductor, the pair are said to beinductively coupled. An electric load wired in series with such asecondary inductor may draw energy from the power source when thesecondary inductor is inductively coupled to the primary inductor.

In the inductive power outlets 6, primary inductors 7 are wired to apower source, such as the electric mains for example, via a controller.The controller provides the electronics to drive the primary coil. Suchelectronics may include, for example, a switching unit providing a highfrequency oscillating voltage across the primary inductor for drivingsame.

Electrical devices 4 may receive power from the inductive power outletsvia secondary inductors 5 configured to inductively couple with theprimary inductors 7 of the inductive power outlets 6. As will beoutlined in greater detail below, in some embodiments of the disclosure,secondary inductors 5 may be housed in inductive receiving units wiredto the electrical devices 2. In other embodiments, secondary inductorsmay be incorporated into the electrical devices themselves.

According to various embodiments of the disclosure, inductive poweroutlets may be incorporated into prefabricated building materials. Withreference to FIG. 2, a plasterboard panel 100 in accordance with oneembodiment of the disclosure is shown. The plasterboard panel 100consists of a layer of building material 102, such as gypsum or thelike, sandwiched between facing sheets 104, 106, that are typically ofpaper. Built into the plasterboard panel 100 are one or more primaryinductors 108A-F and connecting wires 110, 112 that extend to the edgeof the panel 100 allowing it to be coupled to a mains power supply (notshown).

If bulky, the primary inductors 108A-F may be embedded within thebuilding material 102. However, it will be appreciated that the primaryinductors such as inductive coils 108A-F may be relatively thin and maysimply be adhered or stuck onto the facing sheet 104 designed to be theouter facing surface of the panel 100.

The primary inductors 108 a-f and conducting wires 110, 112 may befabricated from wires or metal foil, such as an aluminum or coppersheet. Alternatively, the primary inductive coils 108 a-f and conductingwires 110, 112 may be printed or painted onto the facing sheet 104 usingconductive inks.

Flux guidance cores may improve the electromagnetic coupling of primarycoils 108 with secondary coils 604 (FIG. 6) brought into proximity withthem. In certain embodiments of the disclosure, flux guidance cores (notshown) for example of ferrite or amorphous ferromagnetic material areassociated with each primary coil and embedded in the walling. Furthercomponents such as ferromagnetic shielding elements or the like mayadditionally be incorporated therein.

With reference to FIG. 3, the plasterboard panel 100 may be incorporatedinto a wall 200, such as a standard drywall comprising panels 202 ofplasterboard mounted onto a framework 204.

For use in bathrooms and the like, the plasterboard panel 100 mayusefully be fabricated from ‘green’ water-resistant plasterboard.Indeed, it will be appreciated that the term plasterboard is used ratherloosely herewith and may refer to other building materials, particularlythose used for dry-walling, such as gypsum, plasterboard, gyproc,sheetrock or the like.

Reference is now made to FIG. 4 showing a partially unrolled roll ofwallpaper 300. The wallpaper 300 comprises a flexible sheet 302 of alaminar material that is typically a paper or fabric, the front surface301 of which may be printed or patterned. On the back 304 of theflexible sheet 302, a plurality of primary inductive coils 308 areprovided. The primary coils 308 may be fabricated from a metal foil andadhered onto the flexible sheet 302, or may comprise conductive inksprinted onto the flexible sheet 302 by silk screening for example.

With reference to FIG. 5, the wall paper 300 is designed to be stuckonto the surface of a wall 400. The primary coils 308 are configured toinductively couple with secondary inductive coils 602 (FIG. 6). Suchsecondary inductive coils 602 may be carried by power adaptors 420 usedto provide power outlets attached to the surface 402 of the wall 400;with secondary inductive coils wired to electrical devices, such aslight fixtures 460 or televisions 480, for example; or on furniture suchas tables and the like (not shown), brought into proximity with thewall, and having conventional power sockets or inductive power outletsthereupon.

Power adaptors 420 may be secured to walls 400 using adhesives, or maybe screwed or bolted into place. Alternatively, magnets may be embeddedinto the wall to magnetically couple with corresponding magnets withinthe power adaptors 420. Power adaptors 420 may be readily exchangedbetween different power points without the need for additional wiring.It will be appreciated that power adaptors 420 may be incorporatedwithin appliances such as a television 480, music system or the like. Itis further noted that a single appliance such as a television 480 mayspan more than one primary inductive coil 308, thereby allowing theappliance to draw power from more than one power point. This may beuseful in various applications, such as where the power needed by anappliance is greater than the power that may be supplied by a singleprimary inductive coil 308, for example.

Referring back to FIG. 4, the material from which the flexible sheet 302is fabricated may usefully be heavily patterned or textured to concealelectrical components thereunder, such as primary inductive coils 308 onthe back thereof, and electrical conducting strips 310, 312 extending tothe edge of the paper 300 for coupling to a mains power supply.

Optionally, the paper 300 has an adhesive surface 306 on the backsurface thereof, for adhering to a wall 400. Self-adhesive, pre-gluedwallpapers per se. are known, and technologies thereof may be adaptedfor the inductive papers described herein. Thus, optionally, a waxyrelease layer or backing sheet 307, such as a low density polyethyleneor the like is adhered to the self-adhesive layer 306. The backing sheet307 may be peeled off, enabling the paper 300 to be adhered to asurface, such as a wall 400, via the adhesive surface 306 therebyexposed. Alternatively the front surface 301 may be coated with a waxyrelease material coating, such that when rolled up the self-adhesivelayer 306 is easily separated manually. Other possibilities will presentthemselves to wallpaper hangers.

Referring now to FIG. 6, in certain embodiments of the disclosure,control boxes 500, may be hard-wired to a ring main 540 to provide theelectronics to drive the primary coils 508 embedded or adhered to thewalling 510. Driving electronics (not shown) may be provided. Forexample, these may include a switching unit providing high frequencyoscillating voltage supply and an outlet selector for selecting thepower outlet to be driven. The control box 500 may be connected to theprimary coils 508 by crimple connectors 520 such as flat PCB connectorsfor example. Optionally connecting power tape 560 may be provided havingno primary inductive coils but having conducting strips (not shown) forconnecting between the walling 510 and a control box 500.

A power adaptor 600 may include a secondary inductive coil 602 hardwired to a conventional power jack 604 to which a conventional powerplug (not shown) may be coupled. Alternatively, the secondary inductivecoil 604 may be hardwired directly to an electric load such as a lightfixture 460 or the like. When the secondary inductive coil 604 in apower adaptor 600 is aligned with a primary inductive coil 508 in thewall 510, power may be inductively transferred between the coils therebyproviding power to a load.

Referring now to FIG. 7 an exemplary configuration of electricalcomponents is shown within a section of power walling 700 according toanother embodiment of the disclosure. A common electrical conductingstrip 710 connects with all the primary inductive coils 708 within acolumn. A control strip 712 consists of a bundle of conducting wireseach of which is connected to only one of the primary inductive coils708. Wherever the power walling is severed, the common electricalconducting strip 710 and the control strip 712 may be connected to acontrol box 500 (FIG. 5). The control strip 712 thus provides a meansfor selectively activating each primary inductive coil individually. Theconfiguration of electrical components described above provides controlof individual primary coils. It will be appreciated, however, thatalternative configurations of electrical components are possible, aswill be apparent to persons skilled in the art.

Typically before plastering over a wall, plasterers tape is used tocover over joints in the plaster board. Plasterer's tape, typically ascrim or hessian paper tape, helps to maintain the integrity of thesurface and reduces the risk of the plaster cracking along the joints.

Self-adhesive plasterer's tape is known, such as that described byStough in U.S. Pat. No. 5,486,394. Stough's tape assists in rapid tapingof seams between adjacent drywall units, and is provided in rolls. Thetape has a first layer of flexible paper material with an inwardlyfacing pressure-sensitive adhesive coating thereon. A second layer ofreinforcing woven fiber material overlies the first layer. A third layerof flexible material overlies the woven fiber material to encapsulatethe fiber material between the first layer and the second layer. Thethird layer has an outwardly facing release coating such that the firstlayer adhesive will releasably engage the third layer for manualseparation of the tape when rolled upon itself. A crease is formed alongthe center of the tape to facilitate positioning of the tape in a wallcorner. The self-release properties of the tape allow it to be easilydispensed and applied without the need to remove a backing. The adhesiveis formulated to maintain adhesion even when wetted by an overlyinglayer of drywall mud. Furthermore the release coating on the third layeraccepts and allows the adherence of drywall mud such as jointingcompound, plaster and the like.

Reference is now made to FIG. 8 a showing a roll of power outlet tape800 incorporating inductive power outlets 842 according to anotherembodiment of the disclosure. The power outlet tape 800 is constructedfrom three layers. The first layer 820 has a pressure sensitive adhesivesurface 822 which may be adhered to a surface such as a wall. The secondlayer 840 holds the electrical components which include a series ofpower outlets 842 and electrical conducting strips 844, 846. The thirdlayer 860 overlies the second layer 840 thereby sandwiching theelectrical components between the first 820 and third layer 860.

The electrical components of the second layer 840 are electricalconducting strips 844, 846 and a series of primary inductive coils 842.The primary inductive coils 842 are configured to inductively couplewith secondary inductive coils carried by power adaptors which may beused to provide power outlets upon the surface of a wall.

The outer surface 862 of the third layer 860 may be coated with a waxyrelease material coating such as a low density polyethylene or the like,such that when rolled up the adhesive surface 822 of the first layer iseasily separated from the outer surface 862 of the third layer 860,typically by hand. Alternatively a releasable cover slip (not shown)covered in a waxy release material may be adhered to the adhesive layer822 to protect the adhesive surface from gathering dust and the like aswell as to prevent the tape 800 from prematurely sticking to objects.

FIG. 8 b shows an alternative embodiment of a power outlet tape 800′comprising a two dimensional array 840′ of primary inductive coils 842′.Three rows of primary inductive coils are provide each having its ownpair of conducting strips 844′a-c, 846′a-c. It is noted that such a rollof tape 800′ may be useful for covering large areas for example tabletops, work surfaces or the like. Thus the alternative power outlet tape800′ may be used to provide an array of remote power points.

With reference to FIG. 9 a, the power tape 800 is shown being applied toa wall 900. Drywall boards 920 of material such as gypsum, plasterboard,gyproc, sheetrock or the like are mounted to a framework 940. In orderto obscure the seams 960 between adjacent drywall boards 920, thesegments of power outlet tape 800 are used to bridge between theadjacent drywall boards 920. The drywall boards 920 and taped seams 960create a substantially flat surface upon which plaster 980 may beapplied. It is noted that plaster 980 containing ferromagnetic materialmay provide additional flux guidance for the inductive couplings. In theprior art the bridging function has been performed by a paper, hessianor other scrim tape with no embedded electrical components.

The ends of the power outlet tape segments may be connected to thecontrol box 500 by means of crimple connectors 520 such as flat PCBconnectors for example. Optionally connecting power tape (not shown) maybe provided having no primary inductive coils but including conductingstrips for connecting between the power outlet tape 800 and a remotecontrol box 500.

Control boxes 500, which are hard wired to a ring main 540, provide theelectronics to drive the primary induction coils 842, such as aswitching unit providing high frequency oscillating voltage supply andan outlet selector for selecting the power outlet to be driven.

Inductive power adaptors are used to provide power to wall-mountedappliances as shown in FIGS. 9 b and 9 c. With particular reference toFIG. 9 b, a fully plastered wall 950 is shown, concealing two segmentsof power outlet tape 810 a, 810 b each having five power points at eachof which is located a primary inductive coil 842 a-j. Each segment 810a, 810 b is connected to a control box 500 a, 500 b which is hard wiredto a ring main 540. Various exemplary appliance units include, interalia: a single jack power adaptor 420, a double jack power adaptor 440,a light fixture power adaptor 460 and a wall mounted television 480.Power adaptors 420, 440, 460 may be secured to the walls using adhesivesor screwed into place. Alternatively, magnets may be embedded into thewall to magnetically couple with magnets in the adaptors 420, 440, 460.The power adaptors 420, 440, 460 are thus readily exchanged betweenpower points without the need for any further wiring.

It will be appreciated that power adaptors may be embedded in appliancessuch as a television 480, a music system or the like. It is noted that asingle appliance such as the television 480 shown in FIG. 9 b may spanmore than one primary inductive coil 842 g, 842 h, thereby allowing theappliance to draw power from more than one power point if required, forexample where the power needed is greater than the power supplied by asingle primary inductive coil 842.

Referring to FIG. 9 c, a representation of an inductive power adaptor600 is shown coupled to a power point 842 along a segment of poweroutlet tape 810 which is connected to a control box 500. In the poweradaptor 600 a secondary inductive coil 602 is hard wired to aconventional power jack 604 which may be coupled to a conventional powerplug. Alternatively, the secondary inductive coil 604 may be hardwireddirectly to an electric load such as a light fixture or the like. Whenthe secondary inductive coil 604 in a power adaptor 600 is aligned witha primary inductive coil 842 in the power outlet tape 800, power may betransferred between the coils thereby providing power to a load.

Two embodiments of the power outlet tape are shown in FIGS. 10 a and 10b. Referring particularly to FIG. 10 a, in the first embodiment, theelectrical components 840 are configured such that a common electricalconducting strip 844 connects with all the primary inductive coils 842along the tape. Such a control strip 846 may consist of a bundle ofconducting wires each of which is connected to only one of the primaryinductive coils 842.

A segment of the power outlet tape is detached from the roll, bysevering the tape, perhaps by manual tearing or by using a cuttingimplement such as a pair of scissors or a knife. Wherever the poweroutlet tape is severed, the common electrical conducting strip 844 andthe control strip 846 may be connected to a control box 500. With thisfirst configuration, the control strip 846 may be used to selectivelyactivate each primary inductive coil 842.

A second embodiment of the electrical components 640 of the power outlettape is shown in FIG. 10 b. Here, each primary inductive coil 642 isconnected to its own pair of dedicated conducting strips 644, 646. Theconducting strip pairs from each primary inductive coil 642 extend alongthe power outlet tape for a length sufficient that severing the tapealong any line provides access to three pairs of conducting strips.Thus, severing the tape of the second embodiment along the line A forexample provides contacts to the pairs of conducting strips 644 b-d, 646b-d controlling each of the following three primary inductive coils 642b, 642 c, 642 d. Whereas severing the tape of the second embodimentalong the line C for example, provides contacts to the pairs ofconducting strips 644 d-f, 646 d-f controlling each of the nextfollowing three primary inductive coils 642 d, 642 e, 642 f. It will beappreciated that, although only three primary inductive coils may beindividually controlled in the power outlet tape shown here, the numberof individually controllable primary inductive coils depends upon thelength of the extension of the conducting strips 644, 646. Thus a rangeof tapes may be provided with varying conductor extension lengths forproviding different numbers of individually controllable primaryinductive coils.

Now U.S. Pat. No. 6,444,962 to Reichelt, incorporated herein byreference, describes a heating arrangement that consists of at least oneheating element in the form of a flat element with two opposite-lying,essentially parallel conductors and a coating arranged therebetween forthe generation of electromagnetic waves. The coating material iscomprised of a binding agent, an insulating agent, a dispersion agent,water and graphite. The heating device also comprises a control devicewith a harmonic generator containing an electric component that has arapid rate of current rise and is suitable for generating a highharmonic content. The harmonic generator is coupled to both electricconductors of the heating element in order to emit a spectrum ofvibrations in natural molecular frequency ranges. A low-cost, highlyeffective heating system is thus provided, which, in one embodiment, isa flat panel that can be provided in coiled up form similar towallpaper. Thus flat, wall mounted heating elements that may beincorporated within wallpaper are known.

Referring back to FIG. 1, it has been surprisingly found to beadvantageous to provide inductive coils 6 or ferromagnetic shieldshaving relatively high internal resistance, such that in addition toinducing an electrical current, the oscillation of an electrical currenttherein additionally produces a heating effect. Such a heating effectmay be used as a convection heater for heating the room 1, and usefully,inductive coils having high resistivity are situated under the floor 2 dor beneath a window, thereby facilitating effective heat circulation inthe room.

In open plan areas, such as offices, factory work floors, exhibitionhalls, warehouses and the like, it is often to provide power toelectrical devices at a distance from the walls. To avoid trailingwires, power may be provided from floor mounted or ceiling mountedsockets, however both of these approaches are problematic. Prior artfloor mounted plugs and cables may be kicked or knocked which may damagethe connections and even cause injury to bystanders and in manysituations it is desirable for the floor to be kept clear of powersockets and trailing wires. Overhead power provision require cables tobe lowered from the ceiling which may be unsightly and is impracticalwhere the ceiling is high, such as in large halls and auditoria or foroutdoor use, where there is no ceiling.

Referring to FIG. 11, a solution to the above problem is proposed,wherein floor mounted inductive power outlets 1200 are wired viaunderfloor wiring 1220 to a power source (not shown) either directly orvia a control unit (not shown). The primary inductive coil units 1200are configured to inductively couple with secondary coils 1300 placedthereabove, that are themselves coupled to electrical loads 1320, 1325.In this manner, open floor sockets are avoided. It will be appreciatedthat the system 1100 as herein described may be used with a variety offlooring types such as rugs, fitted carpet, parquet, linoleum, floortiles, tiling, paving and the like.

Floor mounted devices 1320, such as a standing lamp 1320 a or aphotocopier 1320 b, with secondary power coils 1300 in the bases thereofmay be situated directly above the floor mounted primary coils 1200.Alternatively furniture 1325 such as a desk 1325 a or a chair 1325 bwith secondary coil 1300 therein may be placed over the floor mountedprimary coils 1200 and may serve as platforms for providing power toelectrical devices 1340 placed thereupon such as a reading lamp 1340 a,or desktop appliances 1340 such as a laptop computer 1340 b or a noveltycoffee mug 1340 c which directly heats the liquid therein.

Such devices 1340 may be hardwired to furniture 1325, plugged intosockets (not shown) on the table top or may themselves include secondarycoils 1500 and interface with primary coils 1400 on the surface of thetable top 1326.

Other electrical devices into which secondary coils 1200 may beincorporated for aligning with primary coils 1200 of the system 1100include household appliances such as standing lamps, televisions, musiccenters, video recorders, DVDs, and, if suitable wattage is madeavailable, even washing machines, clothes dryers and the like, as wellas cooking appliances such as ovens, cookers, hot-plates, fridges andfreezers for example. In the workplace, the system 1100 may be providedto power typically floor mounted devices such as paper shredders, fans,photocopiers, computers, printers or heavy machinery.

It is further noted that furniture 1325 may be provided with primarycoils 1400 incorporated therewithin for coupling with secondary coils1500 associated with worktop appliances. Furniture into which suchprimary coils may be embodied includes chairs, tables, workbenches,partitioning walls, cupboards or such like.

Worktop appliances having integral secondary coils 1500 which may bealigned with the primary coils 1400 incorporated within a tabletop 1326for example include desk lamps, ambient lighting units, fans, wirelesstelephones, speakers, speaker phones, conference call base units,electric pencil sharpeners, electric staplers, display devices,electrical picture frames, VDUs, projectors, televisions, videos, musiccenters, computers, calculators, scanners, printers, fax machines,photocopiers, paper shredders, hot plates, electrically heated mugs andmobile phones.

There are a number of electrical appliances for personal hygiene thatare often used in the privacy of the bathroom. These include shavers,toothbrushes, hair-dryers, hair curlers and the like. Other electricaldevices are also found in the bathroom, including heaters and lights.Water and electricity should be kept separate however. Electrocution inbathrooms is a real risk, and light switches are usually either locatedoutside the bathroom, or are ceiling mounted with pull cords. Theseissues may be addressed by battery powered appliances, having disposableor rechargeable batteries. However, disposable batteries are expensiveand ecologically damaging. Neither disposable nor rechargeable batteriesare particularly reliable in that they seem to run out of power in themiddle of tasks.

Bathroom walls are often tiled with ceramic tiles and sink surrounds aretypically fabricated from natural or artificial polished stone,stainless steel, ceramic, or acrylics to provide easily cleaned surfacesthat may be repeatedly washed. For safety, bathroom electricity socketsare typically covered with waterproof coverings. It will be appreciatedthat power outlet sockets, are less easily cleaned than suchwork-surfaces, since the socket holes for plug pins, and switches mustbe kept dry to prevent short circuits, or worse, electrocution.

By providing power to appliances via an inductive couple, the risk ofelectrocution within the bathroom can be minimized. Indeed, someappliances may be used within the bath.

With reference to FIG. 12 a, a schematic representation of an electricalappliance, such as a music player 2010 is shown. Instead of having aplug on a flex for plugging into a power outlet socket, a secondary coil2012 is provided in the base 2014 thereof. The electrical appliance 2010may be powered by placing it on a surface 2016, such as a sink surround,incorporating a primary inductive coil 2018, so that the secondary coil2012 is aligned with the primary coil 2018.

The primary coil 2018 is wired to a power supply 2019 via a driver 2017which provides the electronics to drive the primary coil 2018. Drivingelectronics may include a switching unit providing a high frequencyoscillating voltage supply, for example.

It will be appreciated that apart from a music player 2010 this poweringsolution may be appropriate to a wide range of other appliances andgadgets such as hairdryers, shavers, delapidators, heaters, wax-meltingequipment, hair curlers, beard trimmers, bathroom-scales, televisions,radios etc. The primary coil may be concealed behind a facing layer 2015of the bathroom surface, such as a ceramic sink surround or wall tile.The primary coil may also be incorporated in the wall or door of abathroom cabinet, behind a vinyl or Formica surface layer, for example.Similarly, a primary coil may be concealed beneath or within the floorsuch as under or within a rug, fitted carpet, parquet, linoleum, floortiles, tiling, paving and the like, enabling an appliance to be placedon the floor and operated without being plugged in by a visible powercord. Indeed, the primary coil may be incorporated within a sink orbathtub, whether ceramic or acrylic.

FIG. 12 b is a schematic representation of an electrical appliance 2210having a secondary coil 2212 connected therewith via a flex 2211, with avacuum sucker arrangement 2213 for attaching the secondary coil 2212 toa surface 2026, over a primary coil 2218 therewithin. The primary coil2218 is connected to a power supply 2219 via a driver 2217.

It will be appreciated that bathroom surfaces are often smooth, enablingthem to be easily wiped clean. This feature enables suckers 2213 to beused to temporarily attach lightweight objects to bathroom surfaces2216. Optionally, one or more suckers 2213 are provided in proximitywith the secondary coil 2212, for attaching the secondary coil 2212 overthe primary coil 2218.

With reference to FIG. 12 c, occasionally shower jets are inadvertentlydirected at light fittings 2310. Where such light fittings are mainspowered, this could result in electrocution, and bathroom light fittingsshould be fully enclosed. It will be appreciated that light fittings2310 in accordance with embodiments of the present disclosure may befully insulated from the power source 2302 by a dielectric material2304, and provided with a secondary coil 2312. The primary coil 2318 maybe incorporated within green, i.e. water-proof plasterboard 2320, forexample. Thus an alternative, safe approach to providing light in thebathroom is provided.

With reference to FIG. 12 d, a drawer 2400 in a bathroom cabinet 2405 isshown. Drawer 2400 is provided with one or more primary coils 2418.Indeed, the base 2404 thereof may be covered with one large rectangularprimary coil 2418 coupled to a mains power supply (not shown). Aplurality of rechargeable appliances such as electrical toothbrushes2424, hair dryers 2426 and shavers 2428 may be recharged by providingthe appliances with secondary coils (not shown) and placing them withinthe drawer 2400.

With reference to FIG. 12 e, additionally or alternatively, a dedicatedstand 2500 may be provided, with dedicated primary coils 2518 thereonfor recharging specific appliances. For example, a toothbrush holder2500 with a primary coil 2518 therein may be provided for recharging oneor more electrical toothbrushes 2524 storable therewithin, via asecondary coil 2512 thereupon.

With reference to FIG. 12 f, a digital bathroom scales 2600 with asecondary coil 2612 therebeneath may be positioned over a primary coil2618 embedded in the floor 2620, or placed under a bathmat (not shown).

Thus some embodiments of the present disclosure do away withconventional power outlet sockets in the bathroom, which are difficultto clean and have an inherent risk of electrocution.

Certain appliances, such a refrigerators, freezers, stoves anddishwashers are power hungry, large devices that tend to be plugged intodedicated sockets, and are rarely moved, apart from to allow cleaning ofthe space thereunder and therebehind. Such devices are well served byconventional, conductive power technology.

Many other domestic kitchen appliances and gadgets, such as egg beaters,bread-makers, liquidizers, orange juice extractors, vegetable juicers,food-processors, electric knives, toasters, domestic sterilizerssandwich toasters, popcorn makers, magnetic stirrers, waffle makers,electrical barbecue grills, slow cookers, hot-plates, deep-fat fryers,electrical frying pans, knife sharpeners, electrical tin-openers and thelike, are used occasionally, and may be stored in cupboards when not inuse, to keep work-surfaces available for the job in hand.

Ideally, such devices should be usable on any available work surface,including the draining board by the sink, countertops, table top and thelike. The well designed kitchen of the prior art has double power outletsockets set into the walls above all such work-surfaces, enabling suchoccasionally used devices to be plugged in and used where desired.

Kitchens, which are used for the preparation of food for humanconsumption, should be kept hygienically clean. Walls are often tiledwith ceramic tiles and counter tops are typically fabricated frompolished stone, stainless steel, or Formica, to provide an easilycleaned surface that may be repeatedly washed. It will be appreciatedthat power outlet sockets, are less easily cleaned than suchwork-surfaces, since the socket holes for plug pins, and switches mustbe kept dry to prevent short circuits, or worse, electrocution.

Kettles are particularly problematic, as they need to be regularlyrefilled from the tap (faucet). For safe usage, the kettle should bedisconnected from the electric power supply, and in properly designedkitchens, sockets are not located close to sinks, and kettle wires arekept short. To avoid bringing the cord with plug attached to the sink,which is hazardous, the cords of kettles can usually be disconnected atthe point of connection to the kettle. Should this point of connectionget wet however, there is a real danger of short-circuiting and blowingor tripping a fuse, which is inconvenient, and also prevents a realdanger of electrocution which is rather more serious.

For some applications, these issues may be addressed by battery poweredappliances, having disposable or rechargeable batteries. However,disposable batteries are expensive and ecologically damaging. Neitherdisposable nor rechargeable batteries are particularly reliable in thatthey seem to run out of power in the middle of tasks, and for high powerrequiring devices such as kettles and deep fat fryers, battery power isnot a practical option.

With reference to FIG. 13 a, a schematic representation is shown of anelectrical appliance 3120, specifically, a toaster. Instead of having aplug on a flex for plugging into a power outlet socket as withconventional appliances, a secondary coil 3124 is provided in the base3122 thereof. The electrical appliance 3120 may be powered by placing iton a work surface 3140 incorporating a primary inductive coil 3144, sothat the secondary coil 3124 is aligned with the primary coil 3144.

It will be appreciated that although a toaster is described herein byway of an example, the electrical appliance 3120 may be any of a widerange of appliances or gadgets such as egg beaters, bread-makers,liquidizers, orange juice extractors, vegetable juicers,food-processors, electric knives, sandwich toasters, waffle makers,electrical barbecue grills, slow cookers, hot-plates, deep-fat fryers,electrical frying pans, knife sharpeners and domestic sterilizers,kettles, urns, radios, cassette players, CD players and electricaltin-openers.

The primary coil 3144 is wired to a power supply 3160 via a driver 3180which provides the electronics to drive the primary coil 3144. Drivingelectronics may include a switching unit providing a high frequencyoscillating voltage supply, for example.

The primary coil 3144 may be concealed behind a facing layer 3142 of thekitchen work-top, or table. The facing layer may be a sheet of stickyback plastic, vinyl, Formica or wood veneer, for example. Similarly, aprimary coil may be concealed beneath or within the floor such as underor within a rug, fitted carpet, parquet, linoleum, floor tiles, tiling,paving and the like, enabling the domestic appliance to be placed on thefloor and operated.

In one embodiment, primary coils may be placed into a resin that hardensas artificial marble, which is a polymer matrix composite includingmineral filler, such as solid surface building materials, for exampleCorian® or the so-called, Caesar® Stone, manufactured in Israel. Caesar®stone may be cast with sinks and drainers built in. Unlike real stonethat needs drilling from behind to provide a primary inductive coil nearthe upper surface thereof, where desired, Caesar stone and similarcomposite materials, including concrete, may be cast around inclusionssuch as metal objects including inductive coils and connecting wires.

FIG. 13 b is a schematic representation of an exemplary electricalappliance 3120, again represented by a toaster, having a secondary coil3124 connected therewith via a flex 3126, with a vacuum suckerarrangement 3128 for attaching the secondary coil 3124 to a work-surface3140, over a primary coil 3144 therewithin.

As with the embodiment of FIG. 13 a, the primary coil 3144 may beincorporated within a horizontal surface 3140, such as a kitchenworktop. Alternatively, the primary coil may be concealed behind orwithin a vertical surface such as a wall of a building or a cabinet, forexample within ceramic wall tiles, behind wallpaper behind a Formicacupboard door or wall, or the like.

Kitchen surfaces are often smooth, enabling them to be easily wipedclean. This feature enables suckers or suction cups to be used totemporarily attach lightweight objects to kitchen surfaces. Optionally,one or more suckers or suction cups 3129 are provided for attaching thesecondary coil over the primary coil.

The appliances of FIGS. 13 a and 13 b may additionally include a socket3128 for connecting a power cable for conductive power supply, byplugging into a conventional, conductive mains power socket.

Alternatively, as shown in FIG. 13 c, a retractable cord 3123 that iscoilable within the base 3122 of the appliance 3120 c is provided.Furthermore, as shown in FIG. 13 c, but equally applicable to appliances3120 a and 3120 b of FIGS. 13 a and 13 b, a power storage means 3125 maybe provided, for storing power, enabling the device to be charged andused where no inductive or conductive power is available. This makesappliances in accordance with the disclosure, truly portable, and usableon any work surface.

Now, generally lead acid accumulators such as used in cars, are designedto produce a high current burst, whereas rechargeable batteries areessentially designed for powering electronic devices such as mobilephones and laptop computers over extensive periods of time. Embodimentsof the present disclosure are directed to appliances includingcapacitors or electrochemical power storage devices designed to provideappropriate power to power electrical motors for a number of seconds totwo or three minutes, and are thus appropriate for powering foodprocessors, toasters, kettles, and the like.

With reference to FIG. 13 d, a storage area 3000, such as a drawer orcupboard having primary charging coils 3121 in the base thereof isshown. Appliances with a chargeable component 3125 (FIG. 13 c) may bestored in storage area 3000, for removal therefrom and use. In this waythe chargeable component 3125 is fully charged when needed.

In the power providing systems above described, the power outlets aregenerally fixed in predetermined locations. According to otherembodiments of the present disclosure, the power outlets are movable tosuit changing requirements. With reference to FIG. 14 a, a movable poweroutlet 4100, according to another embodiment of the present disclosureis shown, for providing power to an electrical device, specifically acomputer 4182. A primary coil 4120, adjacent to the back face 4142 of asurface layer 4140, is affixed to a positioning mechanism 4160. Theprimary coil 4120 is configured to inductively couple with a secondarycoil 4180 wired to the computer 4182. The positioning mechanism 4160 isconfigured to move the primary coil 4120 behind the surface layer 4140so that the primary coil 4120 may be repositioned.

The primary coil 4120 is wired to a power source typically via acontroller (not shown) providing the electronics to drive the primarycoil 4120. Driving electronics may include a switching unit, providing ahigh frequency oscillating voltage supply, for example.

In some embodiments of the disclosure, the power outlet 4100 may beincorporated into a vertical surface such as a wall of a building or acabinet. The primary coil 4120 may be moved behind a surface layer 4140of wall paper or stretched canvas for example. Alternatively the poweroutlet 4100 may be incorporated behind a facing layer of a horizontalplatform such as a desk-top, a kitchen work-top, a conference table or awork bench for example of mica, Formica or wood veneer. In otherembodiments the primary coils 4120 are configured to move beneathflooring such as rugs, fitted carpet, parquet, linoleum, floor tiles,tiling, paving and the like.

Referring now to FIG. 14 b, according to a first embodiment of thepositioning mechanism 4160, the primary coil 4120 is sandwiched betweenthe surface layer 4140 and a base layer 4162. The primary coil 4120 isaffixed to a carriage 4161, mounted upon a roller-ball 4163 and isconfigured to roll over the base layer 4162. A magnetic element 4166,such as iron, steel or a permanent magnet, is affixed to the carriage4161. The magnetic element 4166 is configured to be pulled by a nearbyattracting magnetic element 4168 situated upon the front face 4144 ofthe surface layer 4140. Moving the attracting magnetic element 4168across the plane of the surface 4140 drags the magnetic element 4166,thereby dragging the primary coil 4120 beneath the surface layer 4140and positioning it as required.

It will be appreciated that instead of the roller-ball 4163, thecarriage 4161 may be mounted upon other elements such as wheels, skis,levitating magnetic elements or the like. Where applicable, movement ofthe positioning mechanism 4160 may further be assisted by coatingabutting surfaces with low-friction materials, such as Teflon® (PTFE).

In a second embodiment of the positioning mechanism 5160, as shown inFIG. 15 a, a primary coil unit 5120 is slidably mounted to a rail 5162.The rail 5162 may run horizontally behind the skirting board 5141 of awall 5140 for example. The primary coil unit 5120 is configured to bemovable into various positions along the rail 5162. The primary coilunit 5120 may be pulled manually by magnets as in the embodiment of FIG.15 a. Alternatively the primary coil unit 5120 may be mounted uponmotorized wheels 5164 and configured to drive itself along the rail5162.

It will be appreciated that the rail 5162 may be straight or curved andmay even snake back and forth to cover an extended area of the wall5140, as shown in FIG. 15 b. According to still other embodiments, morethan one primary coil units 5120 b may be independently positionable.Alternatively a plurality of primary coil units may all be movedtogether.

Reference is now made to FIG. 15 c showing a third embodiment of thepositioning mechanism 5160 c in which a primary coil unit 5120 isslidably mounted to a boom rail 5162, which is slidably supported by apair of generally perpendicular supporting tracks 5164 to form anadjustable H-frame 5165. Thus the position of the primary coil unit 5120may be moved behind a surface layer 5140.

It will be appreciated that in embodiments where the positioningmechanism 5160 is orientated vertically, behind a vertical surface layer5140 such as a wall say, the supporting tracks 5164 may be replaced bysupporting pulleys. Such pulleys may be used to support the boom rail5162 which may be lowered and raised by adjusting the pulleys eithermanually or by a driving motor. Alternatively, the primary coil unit5120 may be suspended from a pulley mounted to trolley configured to runhorizontally along a fixed gantry beam spanning the width of the wall.

According to a fourth embodiment of the positioning mechanism 5160 d, asshown in FIG. 15 d, a primary coil unit 5120 is affixed to four guidingcables 5162 a-d. The lengths of the guiding cables 5162 a-d areindependently controlled by pulleys 5164 a-d, located at four pointsdefining the corners of a quadrilateral 5166. The position of theprimary coil unit 5120 may be manipulated by the pulleys 5164 into anyposition within the quadrilateral 5166. It will be apparent that otherconfigurations of three or more pulleys may be used to manipulate theprimary coil unit 5120 over two dimensions and two or even one pulleymay be used to manipulate a primary coil unit along a line.

Referring now to FIG. 16 a, in a further embodiment of the disclosure,the primary coil 6120 is adjacent to the back face 6142 of the surfacelayer 6140 and is configured to inductively couple with a secondary coil6180 located upon the front face 6142 of the surface layer 6140. Thesecondary coil 6180 may be wired to an electrical device such as a lightbulb 6184 for example.

In order to maximize the inductive coupling between the primary coil6120 and the secondary coil 6180, the gap between them should beminimal. Therefore the primary coil 6120 may be pressed tightly againstthe back face 6142 of the surface layer 6140. A clutch may be provided,such as a compressed helical spring 6122 for example, which urges theprimary coil 6120 towards the back face 6142. Optionally, recesses maybe cut into the back plate 6142, providing bays 6146 therein, whereinthe thickness of the surface layer 6140 is reduced. The primary coil6120 may be docked at one of these bays 6146 for efficient inductivecoupling by minimizing the thickness of the dielectric layer betweenprimary 6120 and secondary coil 6180. A flux guidance core 6124, forexample comprising ferromagnetic material such as ferrite, may beincorporated into the primary coil 6120, the secondary coil 6180 or evenwithin the surface layer 6140 to optimize the inductive coupling.

Pressing the primary coil 6120 against the back face 6142, however,increases the friction between them and may impede the movement of theprimary coil 6120. Therefore, a releasing mechanism 6130 may be providedto disengage the primary coil 6120 from the back face 6142. According toone embodiment of the release mechanism 6130, the primary coil 6120 isaffixed to the distal end of a lever 6132 which is configured to pivotabout a point P connected to a carriage 6126. A first attractivemagnetic element such as a permanent magnet 6134 is affixed to theproximal end of the lever 6132 and situated close to the back face 6142of the surface layer 6140.

As shown in FIG. 16 b, the release mechanism 6130 is configured suchthat a second magnetic element 6136, which may be adjacent to the frontface 6144 of the surface layer 6140, may be brought into proximity withthe first magnetic element 6134. The first magnetic element 6134 isattracted towards the back surface 6142 by the second magnetic element6136. The lever 6132 pivots about point P, compressing the spring 6122and disengaging the primary coil 6120 from the back face 6142 of thesurface layer 6140. The carriage 6126 is then free to carry the primarycoil 6120 to a new position as required. It is noted that the firstmagnetic element 6134 and second magnetic element 6136 may also providea positioning mechanism 6160 as described in the embodiment of FIG. 14b.

It will be appreciated that, for automated systems, one embodiment ofthe release mechanism 6130 may include electromagnets mounted to thecarriage 6126 behind the surface layer 6140. The electromagnets may beused to disengage the primary coil 6120 from the back face 6142 therebyserving the function of the magnetic elements 6134, 6136 describedabove.

By not requiring holes for coupling pins, the inductive power outletsdescribed above may be disguised effectively and are less obtrusive thanconventional power outlets. Generally, the fact that socketless outletsare less obtrusive is advantageous. However, being harder to spot thanconventional power outlets has its disadvantages presenting new problemsto be solved. Notably, the user must somehow locate the concealed outletbefore being able to use it.

The problem of locating such sockets is particularly acute where thepower outlets are behind a concealing surface such as a desk top orwall, and mounted upon positioning mechanisms as described above. Wherethe position of a power outlet is adjustable by being mounted on a trackor arm, within a wall cavity or hollow work surface, and where thesurface is opaque, it is not possible to indicate the position of suchpower outlets by making indicative marks on the concealing surface.

With reference to FIG. 17 a a locatable power outlet 7100 is shown inaccordance with another embodiment of the disclosure. The locatablepower outlet 7100 includes a visual display 7110 that may beincorporated into a surface 7140 such as a wall or work surface, forindicating the location of a primary coil 7120 concealed behind thesurface 7140.

The primary coil 7120 is wired to a power source typically via acontroller (not shown) providing the electronics to drive the primarycoil 7120. Driving electronics may include a switching unit providing ahigh frequency oscillating voltage supply, for example.

According to certain embodiments of the disclosure, the power coil 7120may be concealed behind a vertical surface such as a wall of a buildingor a cabinet. The primary coil 7120 may be concealed behind a surface7140 of wall paper or stretched canvas for example. Alternatively theprimary coil 7120 may be concealed behind a facing layer of a horizontalplatform such as a desk-top, a kitchen work-top, a conference table or awork bench for example of mica, Formica or wood veneer. In otherembodiments a primary coil 7120 is concealed beneath flooring such asrugs, fitted carpet, parquet, linoleum, floor tiles, tiling, paving andthe like.

It will be apparent that when the location of the primary coil 7120 isknown, a secondary coil 7180 may be brought into alignment with it, asshown in FIG. 17 b. When so aligned, the primary coil 7120 mayinductively couple with the secondary coil 7180, thereby powering anelectrical device, such as a computer 7182, wired to the secondary coil7180.

In one embodiment, the location of a concealed primary coil 7120 isindicated to the user by a visual display 7110 incorporated within thesurface 7140. The visual display 7110 displays a map 7112 of the surface7140 upon which the location 7114 of the primary coil 7120 is indicated.

Referring now to FIG. 17 c, which schematically shows a power outlet7101 according to another embodiment of the disclosure, comprising anadjustable primary coil 7121, mounted upon an adjustable H-frame 7161and concealed behind a wall. The adjustable primary coil 7121 iscontrollable remotely from a control panel 7111 and the location of theadjustable primary coil 7121 is indicated by the position of a marker7125 upon a map 7123 represented upon a control panel 7111.

It will be appreciated that a control panel 7111 may be a touch screenupon which the marker 7125 is a cursor which may be moved about avirtual map to control a positioning mechanism. The marker 7125therefore both indicates and adjusts the location of the primary coil7121. Alternatively, the control panel 7111 may be a movable mechanicalswitch, the position of which indicates the location of the concealedprimary coil 7121. Although an adjustable H-frame 7161 is representedhere, it will be apparent that other positioning mechanisms may beapplicable.

With reference now to FIG. 18 a a schematic representation is shown of apower outlet 8100 according to yet another embodiment of the disclosure.Power outlet 8100 includes a concealed primary coil 8120 thatincorporates a transmitter, such as a light emitting diode 8110. Alocator beam L is transmitted by the light emitting diode 8110 toindicate the position of the primary coil 8120. The surface 8140 istranslucent to the wavelength emitted by the LED and thus the locatorbeam L may be detected by a photodiode responsive to the wavelength. Ithas been found that Infra-Red radiation emitted by an LED behind a 0.8mm Formica sheet may be detected by standard digital cameras includingdigital cameras of the type incorporated in many modern mobile phones8200, for example.

It is noted that thin layers 8140 of many materials such as plastic,cardboard, Formica or paper sheet, are transparent to infra-red light.Although a light emitting diode 8110 transmitting light in the infra-redregion of the electromagnetic spectrum is invisible to the human eye, itis readily detectable by digital cameras and, if such an infra-red lightemitting diode is incorporated into a primary coil 8120, a standardmobile phone 8200 equipped with a digital camera may serve as a detectorto locate the primary coil 8120. It will be appreciated, however, that asuitably powerful visible light emitter can be used enabling detectionby the naked eye, provided that the covering material selected istransparent/translucent to the specific wavelength at the emissionintensity of the emitter and the thickness of the covering layer 8140.

It will be appreciated that appropriate detectors may be selected andspecified for detecting specific electromagnetic wavelengths, includingultra-violet radiation, micro waves, radio waves or even x-ray orshorter wavelengths and thus as long as embedded electromagnetic signalemitter and detector are considered together, there are a very largenumber of essentially equivalent solutions to this problem. Furthermore,transmitters configured to transmit other types of radiation, includingmechanical vibrations such as both audible and inaudible (e.g.ultrasonic) sound waves, could be used for locating the concealedprimary coil with the appropriate, corresponding detection means.

Reference is now made to FIG. 18 b showing a block diagram representinga power outlet 8101 according to another embodiment of the disclosure. Aprimary coil 8121 is configured to transmit a locator beam L whichcarries an encoded location signal S identifying the location of theprimary coil 8121. A movable primary coil 8121 is connected to a powersupply 8112 via a switching unit 8114 and a microcontroller 8116. Theswitching unit 8114 is configured to intermittently connect the powersupply 8112 to the primary coil 8121 with a bit-rate frequency f. Alocation monitor 8118 monitors the location of the primary coil 8121 andsends a location signal S to the microcontroller 8116. Themicrocontroller 8116 is configured to modulate the bit-rate signal withthe location signal S. The voltage applied to the primary coil 8121 maybe a modulated variable voltage with a frequency f, carrying an encodedlocation signal S. It will be appreciated that the variable voltage mayproduce a radio wave of frequency f which may be transmitted as alocator beam L. Alternatively, the locator beam L may be transmitted bya dedicated transmitter, separate from the primary coil 8121.

A receiver unit 8201 that includes a receiver 8221 may be provided. Thereceiver 8221 may be tuned to receive the locator beam L of frequency f.The received locator beam L signal can be cross-correlated with areference signal of frequency f to isolate the location signal S. Thelocation of the primary coil 8121 may thereby be transmitted to a remotereceiver unit 8201, which may then output the location of the primarycoil unit to a display.

Although a digital bit-rate modulated locator beam L is described in thefourth embodiment hereinabove, it will be appreciated that the locatorbeam L may alternatively be modulated in other ways such as by analogueor digital frequency modulation or by amplitude modulation, for example.

The location monitor 8118 may monitor the location of the movableprimary coil 8121 directly by keeping track of movements of the primarycoil 8121 in relation to some reference points. Alternative externalsensors such as proximity sensors based on infra-red sensors, ultrasonicsensors, magnetic sensors (like Hall probes), inductance sensors,capacitance sensors or the like, may be used to monitor the movement ofthe primary coil 8121 indirectly, by triangulation for example. Aparticular embodiment of the location monitor 8300 is representedschematically in FIG. 18 c. According to the embodiment, the locationmonitor 8300 includes a host 8310 carrying a tracking-signal emitter8320, an array of tracking-signal detectors 8340 a-c and a processor8360. The tracking-signal detectors 8340 a-c are typically arranged inan array having fixed positions relative to each other in communicationwith the processor 8360.

The tracking-signal emitter 8320 may be used to indicate the location ofa variety of hosts. Accordingly, the location monitor 8300 may be usedto monitor the location of any device hosting the tracking-signalemitter 8320, Possible hosts for the tracking-signal emitter 8320 mayinclude a movable inductive power outlet such as described hereinaboveand/or a movable inductive power receiver such as the receiver 602described above in relation to FIG. 6. Other host devices will occur tothe user.

Typically, the tracking-signal emitter 8320 is configured to emit atracking-signal ST which is detectable by the each of tracking-signaldetectors 8340 a-c. The array of tracking-signal detectors 8340 a-c maybe used to determine the location of the tracking-signal emitter 8320relative to the array of tracking-signal detectors 8340 a-c usingtriangulation. Various emitters may be used in the location monitor 8300such as emitters of electromagnetic waves, acoustic waves, ultrasonicsignals and the like as well as combinations thereof.

Each tracking-signal detector 8340 a-c may register the time at which itdetects the tracking-signal ST and communicate this time to theprocessor 8360. The processor 8360 is configured to use this data tocalculate the relative distance of the tracking-signal emitter 8320 toeach tracking-signal detector 8340 and thereby using triangulation tocalculate its relative location. Although an array of threetracking-signal detectors 8340 a-c is described hereinabove, largerarrays may be used in other embodiments for example when the host ismovable over a large region of space, or where the tracking-signal STmay be obstructed.

In various embodiments, the emission-time of the tracking-signal ST mayadditionally be communicated to the processor 8360. The emission-time ofthe tracking-signal ST is the time at which the tracking-signal ST isemitted from its host. Where the tracking-signal emitter 8320 is mountedin a moving power outlet, the tracking-signal emitter 8320 may itself beconnected to the processor 3860 via a communication line 8370 such thatthe emission-time may be communicated directly from the host to theprocessor 3860. Alternatively, data pertaining to the emission-time maybe encoded into the tracking-signal and may be communicated to theprocessor 8360 via the tracker-signal detectors 8340 a-c.

Referring now to FIG. 18 d, an alternative embodiment of the locationmonitor 8300′ is shown in which the tracking-signal emitter 8320′ ismounted upon a movable inductive power receiver 8440. Tracking-signalreceivers 8340′a-d and a processor 8360′ are associated with an extendedinductive power transmission surface 8420 having a plurality ofinductive power outlets 8422. The location monitor 8301 of theembodiment may be used to locate the inductive power receiver 8440relative to the inductive power outlets 8422.

The inductive power receiver 8440 is configured to draw powerinductively from at least one inductive power outlet 8422, interactingwirelessly therewith. It will be appreciated, therefore, that a directconductive communication line between the tracking-signal emitter 8320′hosted by the inductive power receiver 8440 and the outlet-basedprocessor 8360′ is inappropriate for a wireless environment.

In this embodiment, a double tracking-signal may be emitted by dualtracking-signal emitters. According to the embodiment, twotracking-signals ST′, ST″ are transmitted simultaneously: a firsttracking-signal ST′ being a slow traveling wave, typically an acousticwave, and a second tracking-signal ST″ being a relatively fast travelingwave, typically an electromagnetic wave. Because the secondtracking-signal ST″ is a fast traveling wave, the emission-time may berecorded by a timing-detector 8342 positioned such that it receives thesecond tracking-signal near-instantaneously. The emission-time maythereby be communicated to the processor 8360′. The processor 8360′ isconfigured to calculate the position of an inductive power receiver 8440placed in proximity to the inductive power transmission surface 8420.

It is a particular feature of this embodiment that the processor 8300′may be further configured to communicate with an outlet driver 8430.Thus the location of the inductive power receiver 8440 relative to thearray of inductive power outlets 8422 may be communicated to the outletdriver 8430. The outlet driver 8430 may use this information to selectthe appropriate inductive power outlet 8422 to activate. Typically, theinductive power outlet 8422 closest to the inductive power receiver 8440is selected.

It is noted that the spacing between the inductive power outlets 8422determines the ease with which the inductive power outlet 8422 may bealigned to the inductive power receiver 8440. Where the inductive powerreceiver 8440 is placed in between inductive power outlets 8422, theclosest outlet is generally selected. In further embodiments, the arrayof inductive power outlets 8422 may themselves be mounted upon a movableframe (not shown). The movable frame may be used to align the inductivepower receiver 8440 to the closest inductive power outlet 8422.Accordingly, the moveable frame may have a range of movementapproximately of the order of the spacing between the inductive poweroutlets 8422 within the array. Various embodiments of the moving framemay be driven by motors, piezoelectric elements, connected to the framevia force transmission mechanisms such as gears and so on as suitrequirements.

Referring now to FIG. 18 e, another embodiment of the location monitor8300″ is shown. Here the tracking-signal receivers 8340″a-c processor8360″ are associated with an extended inductive power transmissionsurface 8420″ having a movable inductive power outlet 8422″ such as thatdescribed above in relation to FIG. 15 c. Optionally, a communicationline 8570 may be provided between the processor 8360″ and the movableinductive power outlet 8422″. It will be appreciated that, in thisembodiment processor 8360″ may be further configured to determine therequired placement of the movable inductive power outlet 8422″ and todirect the movable inductive power outlet 8422″ accordingly so as toprovide power to the inductive power receiver 8440″.

A high power inductive power outlet, when active, produces a largeoscillating magnetic field. Where a secondary inductor is inductivelycoupled to the primary inductor, the resulting flux linkage causes powerto be drawn into the secondary inductor. Where there is no secondaryinductor to focus the power, the oscillating magnetic field causes highenergy electromagnetic waves to be transmitted which may be harmful tobystanders. In addition, whereas in low power systems excess heat may bereadily dissipated, an uncoupled high power primary coil or itssurroundings may become dangerously hot.

A high power inductive power outlet, when active, produces a largeoscillating magnetic field. Where a secondary inductor is inductivelycoupled to the primary inductor, the resulting flux linkage causes powerto be drawn into the secondary inductor. Where there is no secondaryinductor to focus the power, the oscillating magnetic field causes highenergy electromagnetic waves to be transmitted which may be harmful tobystanders. In addition, whereas in low power systems excess heat may bereadily dissipated, an uncoupled high power primary coil or itssurroundings may become dangerously hot.

Reference is now made to FIG. 19 showing a block diagram of a power-leakprevention system 9000 for an inductive power outlet 9200 that can beswitched on and off, so that the primary coil 9220 therein producesalternating magnetic field only where a secondary coil 9260 ispositioned to withdraw energy therefrom.

The inductive power outlet 9200 consists of a primary coil 9220, wiredto a power supply 9240, for inductively coupling with a secondary coil9260 wired to an electric load 9264. It is a particular feature of thisembodiment of the present disclosure that a circuit-breaker 9280 isconnected in series between the power supply and the primary coil 9220and configured such that, when actuated, it disconnects the primary coil9220 from the power supply 9240.

The primary coil 9220 is typically wired to a power supply 9240 via adriver 9230 which provides the electronics to drive the primary coil9220. Driving electronics may include a switching unit providing a highfrequency oscillating voltage supply, for example. Where the poweroutlet 9200 consists of more than one primary coil 9220, the driver 9230may additionally consist of a selector for selecting which primary coil9220 is to be driven.

It is noted that the circuit-breaker 9280 may be connected between thedriver 9230 and the primary coil 9220, in which case the circuit-breaker9280 disconnects only the primary coil 9220. Alternatively thecircuit-breaker may be connected between the power supply 9240 anddriver 9230, in which case the circuit-breaker 9280 disconnects thedriver 9230 itself, together with any primary coil 9220 connectedthereto.

The circuit-breaker 9280 is typically controlled by a controller 9400configured to receive a primary signal P indicating that the primarycoil 9220 is transmitting power, and a secondary signal S indicatingthat a secondary coil 9260 is inductively coupled to the primary coil9220 and draws power there from. The controller 9400 is typicallyoperable to trigger the circuit-breaker 9280 thereby disconnecting theprimary coil 9220 from the power supply 9240 when a primary signal P isreceived but no secondary signal S is received.

FIGS. 20 a and 20 b are schematic diagrams representing an inductivepower outlet 9201 protected by a local leak prevention system 9001,according to another embodiment of the present disclosure. Withparticular reference to FIG. 20 a, a primary coil 9221 may be concealedbehind a facing layer of a horizontal platform 9641 such as a desk-top,a kitchen work-top, a conference table or a work bench. Such a platformmay be fabricated from a wide range of materials, including mica,Formica or wood veneer, for example.

In other embodiments a primary coil 9221 may be concealed beneath orembedded within flooring materials and coverings such as rugs, fittedcarpet, parquet, linoleum, floor tiles, tiling, paving and the like.Alternatively the primary coil 9221 may be embedded within or concealedbehind a vertical surface such as a wall of a building or a cabinet, forexample behind wallpaper or stretched canvas or the like.

The primary coil 9221 may be used to power an electrical device such asa computer 9262 wired to a secondary coil 9261; the computer 9262 beingplaced upon the platform 9641 such that the secondary coil 9261 coupledto the computer 9262 is aligned to the primary coil 9221 concealedwithin the platform 9641.

In various embodiments of the disclosure, a primary detector 9421 islocated in the locality of the primary coil 9221 and is configured todetect a magnetic field generated by a primary coil 9221 activelytransmitting power. The detector 9421 may function in accordance withone or more of a variety of principles, including, inter alia, magneticsensing means Hall probes, etc. Alternatively, the detector may be aheat sensor or electromagnetic sensor configured to detect one or morescientific effects inherent to or associated with the operation of theprimary coil 9221.

A secondary detector 9441 is also provided, to detect the presence oroperation of the secondary coil 9261. The secondary detector 9441 may dothis by detecting a signal from the secondary coil 9261 or by detectinga signal from the primary coil or from its surroundings that indicatesdirectly or indirectly, the presence or absence of a secondary coilinductively coupled therewith.

The secondary detector may be a heat detector 9441 configured to detecta significant temperature rise in the platform 9641 in the vicinity ofthe primary coil 9221. Alternatively, the secondary detector may be amagnetic sensor, a Hall probe, an electromagnetic sensor, or the like,configured to detect transmissions from the secondary coil 9261.

With reference to FIG. 20 a, a specific configuration is shown, suchthat when a secondary coil 9261 is inductively coupled to the primarycoil 9221, power transmitted by the primary coil 9221 is received by thesecondary coil 9261, thereby powering the electrical device 9262.Consequently, the primary detector 9421 may detect a magnetic fieldgenerated by the primary coil 9221, and send a primary signal P to acontroller 9401 indicating that power is being transmitted by theprimary coil 9221. Because the power is being transferred to theelectrical device 9262, where the secondary detector 9441 is atemperature probe, it detects no significant temperature rise and can beconfigured to send a secondary signal S to a controller 9401 indicatingthat an electric load is inductively coupled to the primary coil 9221,or not to send a signal, thereby providing an equivalent indication,depending on the logic programming of the controller 9401.

Thus, if the controller 9401 receives a primary signal P, indicatingthat power is present in the primary coil 9221, and a secondary signalS, indicating that an electric load is present, it does not trigger thecircuit-breaker 9281 and the primary coil 9221 continues to draw powerfrom the power supply 9241.

When no secondary coil 9261 is inductively coupled to the primary coil9221, as shown in FIG. 20 b, power transmitted by the primary coil 9221is dissipated throughout the platform 9641 as heat. The primary detector9421 again detects a magnetic field generated by the primary coil 9221and sends a primary signal P to a controller 9401 indicating that poweris being transmitted by the primary coil 9221. In this case however, thesecondary detector 9441 does detect a significant temperature rise dueto the heat dissipated throughout the platform 9641 and so sends asecondary signal S indicating that no electric load is inductivelycoupled to the primary coil 9221. The controller 9401 receives theprimary signal P, indicating that power is being generated, and thesecondary signal S, indicating that no electric load is present,consequently the controller 9401 triggers the circuit-breaker 9281thereby disconnecting the primary coil 9221 from the power supply 9241and preventing any further power from being transmitted by the primarycoil 9221.

Referring now to FIG. 21, a schematic diagram is presented showing aplurality of inductive power outlets 9203 protected by a remote leakprevention system 9003 according to a further embodiment of the presentdisclosure. An array of primary inductive coils 9223 are incorporatedwithin a wall 9643 and wired to a power supply (not shown) via a driver9233. The primary coils 9223 are arranged for inductively coupling withsecondary coils 9263 wired to electrical devices, such as a light bulb9262, which are brought into proximity with them.

When a primary coil 9223 is activated, the driver 9233 provides it witha variable voltage oscillating at a characteristic frequency f.Consequently, the primary coil 9223 transmits radio waves at a frequencyof f. The remote leak prevention system 9003 includes a primary detectorsuch as a radio receiver 9423 within range of the wall 9643, tuned todetect radio waves at the characteristic frequency f. Such radio wavesindicate that at least one primary coil 9223 is transmitting.

The power outlet 9203 may additionally include a secondary detector 9443for detecting a secondary coil 9263 inductively coupled to a primarycoil 9223. The power transmission may then be modulated with a secondarytag indicating that a secondary coil 9263 is inductively coupled to theprimary coil 9223.

The primary detector 9423 may then demodulate the radio waves toidentify the secondary tag. If no secondary tag is detected, the primarydetector 9423 will communicate a control signal C to a controller 9500indicating that power is being transmitted by at least one primary coil9223 in the absence of a secondary coil 9260. According to a basicembodiment, the controller 9500 is operable to then trigger a circuitbreaker (not shown) thereby disconnecting all the primary coils 9223.

Alternatively, the driver 9233 may additionally comprise a modulator(not shown) for tagging the power transmissions of each active primarycoil 9223 a-h with a primary tag uniquely identifying the active primarycoil 9223 a-h from which the radio waves are transmitted. The primarydetector 9423 will then detect the primary tag and thereby identifywhich rogue primary coil is transmitting power in the absence of asecondary coil. The primary detector 9423 then communicates this to thecontroller 9500 which disconnects only the rogue primary coil.

A method for preventing an inductive power outlet of embodiments of thedisclosure from transmitting power in the absence of an electric loadcoupled thereto, is presented in the flow chart of FIG. 22. The methodincludes the following steps: a primary coil transmits power; the powertransmission from the primary coil is detected; a secondary detectorsearches for a secondary coil inductively coupled to the primary coil;and the primary coil is disconnected from its power supply if nosecondary coil is detector.

With reference now to the flowchart of FIG. 23, a method is presentedfor transferring power from an inductive power outlet to an inductivepower receiver adjacent to an extended surface. The method includes theprinciple steps of: step (I)—providing a primary inductor behind theextended surface; step (II)—locating the inductive power receiver placedagainst the extended surface; and step (IV)—providing an oscillatingvoltage supply to a local primary inductor coupled to a secondaryinductor associated with the inductive power receiver.

It is noted that, in step (I) various embodiments of the inductive poweroutlet maybe provided. For example, in the embodiment provided in step(I′), an array of primary inductors are distributed behind the extendedsurface. Alternatively or additionally, in the embodiment provided instep (I″), a movable primary inductor is provided behind the extendedsurface.

According to the various embodiments, additional steps may be included.For example, where an array of primary inductors is provided, the methodmay include the additional step (III′) of selecting, from the array, alocal primary inductor in the vicinity of the secondary inductor.Alternatively, or additionally, where a movable primary inductor isprovided, the method may include the additional step (III″) of directingand moving the movable primary inductor into the vicinity of saidsecondary inductor.

It is further noted that optionally, step (II) may involve the substeps:step (IIa)—the inductive power receiver emitting a tracking-signal; step(IIb)—an array of tracking-signal detectors detecting thetracking-signal; step (IIc)—calculating the location of said inductivepower receiver using triangulation.

A number of power providing technologies and configurations have beendescribed and set forth hereinabove. These technologies use inductivepower supply inductors (primary inductors) coupled to secondaryinductors associated with appliances. By virtue of the variousembodiments, conductive power supply with the associated sockets andtrailing wires may be replaced with elegant, solutions. A number ofpower providing technologies and configuration have been described andset forth hereinabove. These technologies use inductive power supplyinductors (primary inductors) coupled to secondary inductors associatedwith appliances. By virtue of the various embodiments, conductive powersupply with the associated sockets and trailing wires may be replacedwith elegant, solutions.

The scope of the present disclosure is defined by the appended claimsand includes both combinations and sub-combinations of the variousfeatures described hereinabove as well as variations and modificationsthereof, which would occur to persons skilled in the art upon readingthe foregoing description. While the best mode has been described indetail, those familiar with the art will recognize various alternativedesigns and embodiments within the scope of the following claims. Whilevarious embodiments may have been described as providing advantages orbeing preferred over other embodiments with respect to one or moredesired characteristics, as one skilled in the art is aware, one or morecharacteristics may be compromised to achieve desired system attributes,which depend on the specific application and implementation. Theseattributes include, but are not limited to: cost, strength, durability,life cycle cost, marketability, appearance, packaging, size,serviceability, weight, manufacturability, ease of assembly, etc. Theembodiments discussed herein that are described as less desirable thanother embodiments or prior art implementations with respect to one ormore characteristics are not outside the scope of the disclosure and maybe desirable for particular applications.

In the claims, the word “comprise”, and variations thereof such as“comprises”, “comprising” and the like indicate that the componentslisted are included, but not generally to the exclusion of othercomponents.

While exemplary embodiments are described above, it is not intended thatthese embodiments describe all possible forms of the invention. Rather,the words used in the specification are words of description rather thanlimitation, and it is understood that various changes may be madewithout departing from the spirit and scope of the invention.Additionally, the features of various implementing embodiments may becombined to form further embodiments of the invention.

What is claimed is:
 1. An inductive power receiver incorporated into abase of a floor mounted device, said inductive power receiver comprisingat least one secondary inductor configured to inductively couple with atleast one floor mounted primary inductor, and to provide power to atleast one electric load.
 2. The inductive power receiver of claim 1wherein said floor mounted device comprises an item of furniture.
 3. Theinductive power receiver of claim 2, said item of furniture beingselected from a group consisting of chairs, tables, workbenches,partitioning walls cabinets and cupboards.
 4. The inductive powerreceiver of claim 1 further comprising a power storage unit configuredto store energy received by said secondary inductor.
 5. The inductivepower receiver of claim 4 wherein said power storage unit is selectedfrom a group consisting of: capacitors, accumulators and electrochemicalcells.
 6. The inductive power receiver of claim 1 further comprising atleast one device-mounted inductive power outlet for inductivelyproviding power to electrical loads.
 7. A power providing systemcomprising at least one inductive power outlet comprising at least oneprimary inductor connectable to a power supply via a driver; said driverconfigured to provide an oscillating voltage supply to the primaryinductor; said primary inductor configured to couple inductively with asecondary inductor wired to an electric load wherein said inductivepower outlet is incorporated into at least one sheet for incorporatinginto a bounding surface of a workspace, said sheet comprising said atleast one primary inductor; and at least one pair of conductors forconnecting said primary inductor to said driver.
 8. The power providingsystem of claim 7 wherein said bounding surface is selected from a groupconsisting of: walls, floors, ceilings, sinks, baths, doors and worksurfaces.
 9. The power providing system of claim 7 wherein said sheetcomprises a prefabricated building material for incorporating into abounding surface of a said workspace.
 10. The power providing system ofclaim 9 wherein said prefabricated materials is selected from a groupconsisting of: plasterboard, paper sheets, wallpaper, plasterers tape,doors, window frames, wall-tiles, fitted cabinets, kitchen counters,sinks, baths, sink surrounds, parquet, linoleum, floor-tiles, non-slipmatting, tiling, stone, artificial stone and paving.
 11. The powerproviding system of claim 7 wherein said primary inductor is covered bya facing material selected from a group consisting of Formica, veneer,plaster, paint, plastic sheet, stone and artificial stone.
 12. The powerproviding system of claim 7 wherein said primary inductor is insertedinto a base material and covered by a facing material.
 13. The powerproviding system of claim 7 wherein said at least one primary inductoris incorporated into an inductively enabled stowage unit and configuredto inductively couple with secondary inductors associated withelectrical devices stowed in said stowage unit.
 14. The power providingsystem of claim 7 further comprising a flux guidance core for directingmagnetic flux from said primary inductor to said secondary inductorcoupled thereto.
 15. The power providing system of claim 7 wherein saidsheet comprises a plasterboard panel comprising a layer of gypsumsandwiched between two paper sheets and at least one pair of conductorsfor connecting said primary inductor to said power supply, said primaryinductor being behind at least one of said paper sheets.
 16. The powerproviding system of claim 15 additionally being characterized by atleast one feature selected from: a ferromagnetic core for improving fluxguidance between said primary inductor and said secondary inductor; atleast one primary inductor being printed onto at least one said papersheet; said panel being water-resistant; said panel comprising a heatingelement; said panel comprising a high resistance primary inductor; andsaid primary inductor comprising an alloy having relatively highresistance such that oscillating currents therein, produce a heatingeffect.
 17. The power providing system of claim 7 wherein said sheetcomprises a paper sheet for adhering to the bounding surface.
 18. Thepower providing system of claim 7 said sheet being characterized by atleast one feature selected from: said sheet being a wallpaper; saidprimary inductor being adhered onto the back of a dielectric layer; saidprimary inductor comprising a conducting coil printed onto paper; andsaid sheet comprising an adhesive layer for self-adhering to saidbounding surface.
 19. The power providing system of claim 7 wherein saidsheet comprises a floor surface for the workspace of claim 1, saidprimary inductor being embedded therein and wired to said power supplyvia wiring thereunder.
 20. The power providing system of claim 19,wherein the floor surface is selected from a group consisting of: rugs,fitted carpets, parquet, linoleum, floor-tiles, non-slip matting,tiling, stone, artificial stone and paving.